They are the same as a whole,their apperance and functions.
But you should note here is that which systems they support.

U8 and U8S just difference between waterproof.

U8S is waterproof,and U8 is not.
Both of U8 and U8S APK does not support IOS system (only support Android system), so customer use iPhone or iPad (IOS system) could not use Remote Camera or SMS Synchronous functions.
Apart that, other functions support IOS system.

U8 and U8L(U8 Plus) difference between support systems.

U8L(U8 Plus) support IOS and Android system and all functions.
U8 APK does not support IOS system in Remote Camera and SMS Synchronous two functions.

These are the few Muslim Apps that would come real helpful especially in Ramazan / Ramadan :

1) My Prayer – صلاتي :

This app calculates Muslims prayer times using the phone’s location (latitude and longitude) based on different conventions.Application Features:
– A widget that shows today’s prayers times.
– A horizontal widget the shows a time bar between the previous and next prayer.
– Notification for each prayer and Iqamah reminders, with the ability to adjust their times.
– Ability to select notification tone (Athan) from the SD card.
– Switching the phone to silent automatically during prayer times, with settings for each prayer.
– Finding the location automatically using Network or GPS, or manually by searching in the Internet.
– A Compass to show the Qibla direction.
– Fajr (and Sahoor) Alarm, and it can be configured from Settings.
– A Date Converter, to convert Hijri to Gregorian and vice versa, and calculate the prayers for that date.
– Ability to adjust prayer times manually.
– Can be used in both languages, English or Arabic, and with two colors, White or Black.

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